Best Lenses for Milky Way Photography: Canon Astrophotographers

The most common question asked on Lonely Speck answered for Canon shooters!

What is the best lens for astrophotography? The one that collects the most light.

Below is a list of the highest scoring lenses for untracked nightscape photography and astrophotography. The score is a direct representation of light gathering capabilities based on the formula:

Score = (aperture area) × (angular area) × (suggested shutter speed)

Where the shutter speed is the longest suggested shutter speed in seconds based on the “500 Rule” (500/focal length). Aperture area is the surface area calculation of the clear aperture of the lens and the angular area is the angular field of view in square radians. This score is a mathematical calculation based purely on some simple physics. It doesn’t account for other considerations like the lens’s build quality or optical aberrations but it’s a good gauge of overall light gathering capability. You can also see the complete list of scores here, complete with calculations and further explanation.

All of the lenses listed here are my personal suggestions for photographers looking to get the absolute best astrophotography results with their camera. If using the given camera mount, these are the lenses that I would use. Most of these lenses are manual focus lenses by Rokinon which also tend to be much more affordable than their autofocus Canon counterparts. Additionally, most of the Rokinon lenses are sharper and tend to exhibit less coma aberration than their Canon counterparts. If you’re willing to learn how to use manual focus, Rokinon lenses are spectacular performers.

This is my go-to lens for astrophotography on a full-frame DSLR. It’s fast, wide and shows very little aberration problems. Still my personal favorite for Canon full frame DSLRs like the 6D, 5D Mark III and 5DS/R cameras.

If your camera has a live mode function then focusing in the dark is quite easy. Switch on the Live view mode (most EOS DSLR’s appear to have this function) and you will see on the rear panel an image of what the lens is seeing. Use the + key to zoom in to a distant light source (start or moon etc) and set the manual focus. Once set you can switch off the live view function and take your photo.

What is your take on the Zeiss Otus 28mm f/1.4 for Astro Photography? Using a Canon 5D Mark IV for other purposes besides Astro. Considering Milvus 25mm f/1.4 at less than half the price. Will track with Astro. Cost for quality glass is substantial. With post techniques, as sophisticated as they are, could I go wrong? There are so many positive comments about the Rokinon 24mm f/1.4. But, looking for a high-end lens that delivers exceptional image quality in 2018, curious if you have not come across a better option than the Rokinon options for FF Canon users. What are your thoughts?

Needing Help – I’m located in Aust, doing a 4 week trip up to the Kimberleys and would love to take some Astro Landscapes! Struggling to find the first lens for the right price.
I was looking at the Canon 16-35mm f2.8 iii USM lens. But super Expensive and I’ve not saved up all that amount!
Got a Canon 1100D and a 6D cameras to take.
Suggestions??
The Rokinon 24mm f/1.4 looks good, But I’m worried about the Manual Focus only… Is this hard to do being with Astro Photography it’s so dark and focusing I find is hard!
Thanks Looking forward to a response!